1. Field of the Invention
This invention relates generally to shade deployment and retraction apparatus and specifically to suspension and actuation apparatus for suspending, deploying and retracting shades or curtains that have been specially produced to cover or otherwise drape openings of unusual and often unconventional shape. Further to this disclosure, stiffening inserts that may be used to rigidify a cellular shade fabric along prechosen margins or cells are exploited.
Of particular interest to the instant inventors is the field of the art that deals with tensioned pulley systems, spacer or spacing suspensions, cord or lanyard attachment means and means that are used for snubbing or otherwise securing cords or single strands that are used to motivate basic shade or curtain apparatus.
2. Discussion of the Prior Art
An examination of the background or prior art is best appreciated after the reader is given some insight into the nature of the instant invention and its application with special materials in a specialized environment. With the advent of multi-cellular, essentially planar curtains, the aforementioned suspension, actuation, etc. systems could be developed for usages that were formerly unavailable to the traditional or more conventional window treatment art such as shades, curtains and window/door/portal coverings. It is because of the fact that the apparatus of the instant invention is distinct from window treatment apparatus that employs only planar shades, pleated curtains, or Venetian blinds that exhaustive searches of the prior art and catalogue literature disclosed no relevant information about the instant invention. For this reason, it was necessary to review patents which deal with actuating and suspension mechanisms for window coverings, and the like, and which embody pleats, multiple slats and multi-cellular shade elements.
The instant inventors' desire to use pleated or multi-cellular shade material or fabric is the reason for the instant invention embodiments and accessories therefor. An understanding, not so much of the physical principles that make multi-cellular fabric so useful, but of its inherent handling and deployment characteristics is necessary to the full appreciation for the aforesaid rationale. To illustrate, by way of contrast, consider the ordinary window shade which consists of a spring biased roller upon which a flat, rectangular fabric is rolled, a rigidified margin at the "pulling" edge of the shade and (usually) a drawstring or finger hoop located either at the middle of the rigid margin, or a plurality thereof (individually) equally spaced along the margin. Irrespective of the manner in which the multiple drawstrings are ganged (drawn together), the reason for their physical embodiment, whether the single-center type or the plural, periodically-spaced type, the drawing selection mode depends entirely upon the physical embodiment of the shade. The single-central draw cannot be used if the rigid margin to which it is centrally attached is missing, because the shade material is completely flexible and will not draw evenly, whether the draw be upward/downward or transversal. If the flat flexible planar shade were cut so as to fill an unusually shaped window, say one of hemispherical cross section, and the hemispherical shade were rolled on a spring-biased roller with a draw located at the zenith of the hemisphere and drawn upward, a clear exception would exist in that such a concept, save for the instant invention, does not appear in the art. Excepted in small part from the previous statement is the patent issued to Phillips in 1970 (U.S. Pat. No. 3,495,606) relating to a Damper Valve for Ventilating Ducts. Phillips, for obvious reasons, employed a rigid shade fabric that could be drawn orthogonally from a diametrical chord to a peripheral boundary of the duct. Philips chose to use a rigid, pleated diaphragm which expands and retracts over the opening of the duct. The deployment and collapse of the damper member is effected along a fixed diametrical, elongate strut which is connected at each of its ends to diametrically opposed lands in the collar of the duct. During normal operation, the Phillips damper is restrained in a collapsed or undeployed configuration until the melting of a fusible link that has been placed strategically in position to both restrain damper closure, yet sense the excessive heat that will cause the link to fuse. Immediately upon fusing of the link, natural resiliency of the damper member urges its constituent hemispherical components toward the closed position; and, retraction therefrom is effected only by physically forcing the damper elements back to the collapsed, damper-open position and reinstalling therewith a new fusible link. For several reasons which are intuitively obvious, the fusible link-controlled damper valve of Phillips, although illustrative of the pleated curtain usage for the covering of circular or semicircular openings, bears no true relevance to the suspension and actuation means of the instant invention.
At this point, discussion has been relegated to the coverage of radiating openings by movable shade apparatus, wherein the movement is essentially translational, that is, straight across a radian. diameter or chord of the curvilinear opening. There exist four pieces of prior art that are deemed by the instant inventors to be germane to the subject of radiating curtains or shades and the installation, supporting and/or actuation mechanisms therefor. The earliest of this art form is exemplified by U.S. Pat. No. 1,609,877, issued to Kendal in December 1926 for a Circle Head Window Shade. In June 1968, Clemens was issued U.S. Pat. No. 3,386,106 for a Shower Curtain Structure; while Karp was issued U.S. Pat. No. 4,745,960 in May 1988 for a Collapsible Partition Assembly. Finally, in this class of art, European patent application No. 8720517.8, Publication No. 0 240 065, was filed on Mar. 20, 1987 for a Folding Curtain Screen Structure for a Triangular Window.
Kendal discloses installation apparatus for a collapsible, pleated semicircular shade which deploys radially from a collapsed position, occupying a single radian, through an arcuate path to full deployment of a semi-circular pattern. In one embodiment, Kendal attaches the semi-circular pleated shade to a rigid sill passing two hoops, one through the pleats of the shade proximate its center and the other adjacent the pleat crests, near the circumferential perimeter thereof. In this embodiment, the central hoop, which is used to guide and sustain the arcuate deployment of the shade, passes through the shade elements and is common to all embodiments taught by Kendal. The outer or circumferential hoop which is used to sustain not only the deployment of the shade, but maintain its rigidity along the peripheral shape of the opening, may be placed through the shade elements proper as is the central or root hoop; or it may be captured by loops or clevises that are secured to the crests of the pleated elements. Again, it is intuitive that, because Kendal works with a fabric that is essentially planar and flexible (albeit pleated), he cannot dispense with the outer peripheral hoop; and thus, must resign himself to the use of suspension, actuation mechanisms and generally apparatus, that remain visible when the shade is collapsed, thus presenting to the viewer a totally non-aesthetic and unappealing image. Because the instant inventor employs a pleated or multi-cellular fabric which is inherently more rigid than planar fabric, it is possible to dispense with the support hoops and attendant deployment apparatus of Kendal and create a resultant product that is aesthetically far more pleasing.
In the patent issued to Clemens for a Shower Curtain Structure, a collapsible, pleated shade is seen to effect, upon deployment, a quarter circle shape. The pleated shade material is affixed at each radial margin to a flange element; and both flange elements are pivotally connected at the center point or radial point of the curtain structure. For all practical purposes, the hinge is conventional and otherwise unworthy of note. Installation of the Clemens curtain is had by affixing one radial flange to a vertical surface and it is thereafter deployed by disconnecting the free end of the other radial flange from its engagement with the wall-mounted flange and "fanning" the curtain radially as the moving flange transits a downward, arcuate path. Collapse or stowage of the deployed shade is effected manually by moving the pivotable flange member back into locked registry with the wall-affixed flange element. Clemens makes no suggestion of a collapse or retraction means for the deployed shade or curtain of this invention. In a situation where a specially designed window, requiring a quarter-round geometry for its respective shade covering is located well above the average head height, the manual stowage and lock/unlock feature of Clemens is completely deficient. Further, the "bunched" ends of the curtain pleats are unsuitable for window coverings as this characteristic does not allow a uniform expansion of the shade. The instant invention provides an excellent solution to the previously mentioned limitations.
In some respects similar to the Clemens invention, Karp teaches the deployment of a pleated shade by the movement of a hinged member through an arcuate path of approximately 90.degree.. A uniquely pleated curtain is disclosed by Karp in order to effect one embodiment of his invention that requires an arcuate deployment of an apparently rectangular fabric. However, the type of shade employed by Karp is not germane, while the means of deployment and retraction bear some relevancy. Karp "lowers" the movable flange element to which one margin of the curtain is affixed. Lowering of the movable flange element is accomplished through use of a winch-type apparatus located at the top of the fixed marginal element through a cord running therefrom to the outer end of the movable margin element. Clearly, the winch apparatus of Karp is totally inapplicable to the needs of the instant inventor and has no more utility than the Clemens closure method.
The European patent application of Niemeijer discloses a novel screen structure for covering a non-rectangular window. Although in some respects relevant, Niemeijer, apparently lacking the pleated or multi-cellular shade fabric used by the instant inventors, has no incentive to utilize the instant invention's apparatus as will be hereinafter disclosed. Instead, Niemeijer employs a distinctive screen structure comprised of overlapping shade segments that are interlinked by a plurality of common cord strands. The strands pass through practically all segments along common locii and are used to gather the shade upward to the shade's fixed radial margin. Although the instant invention contemplates, or at the least would provide a solution to the screening of a triangular shaped window, the method of Niemeijer would be totally inapplicable to the problem solution in the intended environment simply because it makes no attempt to solve the problem using the preferred shade or fabric embodiment of the instant inventors nor, more importantly, deal with curvilinear opening geometries, in general. Relative to actuation devices for generally arcuate, and specifically arch topped shades, apparatus employed by two contemporary inventors appears to be the most relevant. Langeler was issued U.S. Pat. No. 4,473,101 in September 1984 for an apparatus entitled Sun Blind. In December 1985, Judkins was issued U.S. Pat. No. 4,557,309 for a Sun Blind and again, in June 1987 U.S. Pat. No. 4,673,018 for an invention bearing the same title. Although neither of these inventors was concerned with the immediate problem, that of deploying, fixing and retracting between the fully retracted and fully deployed positions a sun screen or curtain made of pleated or multi-cellular fabric, it is nevertheless incumbent upon the instant inventors to discuss certain aspects of these relevant patents because it is evident that they were concerned not so much with the overall appearance of their respective inventions (perhaps to some degree because they look alike), but rather to the method and means for actuating and guiding the shade element therein.
Langeler teaches a sun blind which comprises a horizontal upper bar, serving also as the header of a window frame, and a horizontal bar disposed for movement with respect to the top bar, with lateral guides for guiding the ends of the movable bottom bar. The lateral guides reside within the side posts of the window frame. At least two cords are used to guide the bottom bar while the ends of the cords are fastened to fixed points of either the top bar, the bottom bar or the lateral guides of the apparatus. Notably, Langeler utilizes a plurality of spring tensioners in the form of coil springs to provide tension on the aforesaid cords and locates the individual spring at the end of the cord where it is attached to either the header or sill elements, or the lateral guide bars. The Langeler actuation mechanism, although capable of positioning the curtain, requires a plurality of cords for such positioning. Secondly, it is evident that the purpose of the springs attached at the end of each cord is primarily to prevent overstressing or breakage of the cord upon overloading and, secondarily, for tensioning the cord. Neither the apparatus for deployment nor the cord actuation system of Langeler would function in, nor is it addressed to, the requirements of the instant inventor in providing single point attachment mechanisms for his novel window treatment designs.
Similar to Langeler, Judkins teaches the use of two or more cords, one to support the shade at an angle off the vertical, and the other to move the shade upwards by movement of a cord set (the shade is lowered by gravity). In contrast to the art of both Langeler and Judkins, the instant invention does not rely operationally on gravity (a reliance which may result in damage to either the shade fabric or sills), but is actuated by use of a tension cord. Further, actuation directions may be either vertical or horizontal. This versatility is acquired through the use of a solitary cord, a nuance which appears both novel and, since it has not appeared in patents issued as late as 1987 in the shade art, not obvious. Further, from a careful study of all the prior art, it appears that none of the inventors of the herein-discussed relevant art had any motivation to actuate a curvilinear shade at but a single point. Although the teachings of Karp (infra.) did contemplate a single cord retraction, Karp evidently did not feel impelled to practice the instant invention, nor suggest same, because he was totally satisfied with his winch type retraction mechanism.
Because of the aforementioned critical shortcomings of the prior art, the instant inventors were compelled to develop a unique system of shade deployment and actuation directed towards use of the cellular shade structure. Concomitantly, reinforcement structures were also developed and are offered in several (optional) embodiments. All of these developments serve to epitomize the functionality of the pleated and multicellular shades with which they are employed.